Air nozzles for vehicles are used on a large scale, and due to the large quantities produced and the associated low production costs which are required, it is necessary to carry out a standardization of both the sizes and the types.
On the other hand, different vehicles comprise completely different ventilation situations, so that e.g. a windshield defroster nozzle having a throw distance which is as high as possible has to be constructed totally differently from a legroom air outlet.
In many cases it is desired to influence the outlet of air by the user, for example via a slider, which influences the outlet cross section, or via lamellae, which influence the direction of the outlet of air.
But there are also simpler air nozzles, which are also referred to as air outlets, and which are provided with fixed lamellae and are formed as an integral plastic part, in most cases.
Besides these different requirements which require a considerable variety of production on the part of the manufacturers of air nozzles, automotive manufacturers often proceed to freely locate the desired installation site of the air nozzle.
While typically an installation in a body opening made of sheet steel on the one hand or of sheet aluminum on the other hand does not pose any problems due to the comparatively small difference in thickness of sheet steel and sheet aluminum and as a safe locking is possible through detents known per Se, this does not hold true without further ado for the installation at the dashboard or e.g. at other plastic coverings in a vehicle. There, completely different thicknesses of the base material are used, and sometimes foamed materials are also used, many times for safety reasons, i.e. to keep the risk of injuries as low as possible in case of a possible collision with vehicle passengers.
DE 20 2009 004 949 U discloses an air nozzle comprising a combined screw/lock fastening, wherein the screw is intended to pass through the snap-in tongue.
With the help of the inclined plane at the snap-in tongue a difference in thickness of the installation wall can be compensated. for to a certain extent. However, this compensation is not sufficient to cover the possible installation sites so that in such a nozzle still at least four or five different nozzles of each nozzle type have to be made available in order to cover the possible installation sites.
Pure screw fastening is also possible, as can be seen e.g. from U.S. Pat. No. 6,016,976. In a pure screw fastening it is possible to provide for additional screw holes adjacent to the body opening and to make possible to lock the air nozzle even at an installation from the front side, as is always desired.
However, such additional cutouts in bodies multiply the effort in the production of the body openings and may also pose adjustment and adaptation problems. While in round nozzles that click into place angle errors do not play any role, this does not hold true for screw fastening nozzles as the screw holes have to be in exact alignment with the cutouts for the screws.
For reasons of the simplification of the installment, therefore, snap-lock connections have been desired up to now which are, however, not problem-free either. For instance, DE 102 48 740 A1 (see paragraph [0005] and paragraph [0006]) discusses the problem that protruding snap4n tongues break easily when they are accidentally installed at an angle.                Moreover, snap-in tongues also those comprising slanted planes which should, however, not exceed a certain tilt angle are typically suitable for balancing different thicknesses of metal sheet, but not completely different installation sites.        
Furthermore, DE 10 2006 029 733 A1 discloses an air nozzle which has a relatively flat design, on the one hand, and which is also supposed to cover different material thicknesses, on the other hand. For this purpose, a clamping element with different snap-in elements is provided.
Generally, this solution is well suited for covering different wall thicknesses. It is, however, rather intended for flat and therefore lightweight nozzles, while a fine adjustment is slightly overstrained in the application of larger and heavier nozzles, such as lamellar spreader rolling.
Furthermore, it has already been suggested to use an adjustable sliding mechanism for adapting to different wall thicknesses in the bearing housings for air nozzles, which does not only facilitate the adaptation to different material thicknesses of the dashboard or any other installation site but which can also balance an unevenness to a certain extent. Typically, the bearing flange of the bearing housing has a circular shape while the installation site can in part also be at a curved sheet metal. But still a sealing must be guaranteed, which is a problem to a certain extent. For this purpose, a sealant can for instance be introduced before the installation takes place in order to carry out sealing.
However, a further problem is the tendency of the suggested air nozzles to detach due to the permanent vibrations, because if there is a slight play already, the bearing is burdened to an ever increasing extent, until the air nozzle eventually blocks.